Effect of disc displacement on mRNA expression of urokinase plasminogen activator and its inhibitor-1 in synovial tissues / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of anterior disc displacement on the expression of urokinase plasminogen activator and its inhibitor-1 (uPA/PAI-1) in synovial tissues.</p><p><b>METHODS</b>Forty Japanese white rabbits were used in this study. The animals were killed at 4 days, 1, 2, 4, 8 and 12 weeks postoperatively, respectively. In situ hybridization technology was applied to detect the expression of uPA/PAI-1 mRNA in synovial membrane.</p><p><b>RESULTS</b>In normal synovial tissues, synovial lining cells and a few fibrosblasts with mild positive staining were occasionally seen. More synovial lining cells and fibrosblasts with moderate postive signals were found 1 week after operation. Since then, the degree of staining for uPA/PAI-1 increased gradually. By the end of 12 weeks postoperatively, strong signals of uPA/PAI-1 mRNA were detected.</p><p><b>CONCLUSION</b>There is a harmonized uPA/PAI-1 system existing in synovial tissues. The high expression of uPA and PAI-1 mRNA in synovial tissues indicates that the uPA/PAI-1 system may play an important role in the process of synovitis resulted from anterior disc displacement.</p>

Gene expression of fibrinolytic factors urokinase plasminogen activator and plasminogen activator inhibitor-1 in rabbit temporo-mandibular joint cartilage with disc displacement / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The urokinase plasminogen activator system is believed to play an important role in degradation of the extracellular matrix associated with cartilage and bone destruction; however its precise roles in temporomandibular disorders have not yet been clarified. The aims of this study were to investigate the gene expression of fibrinolytic factors urokinase plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in the articular cartilage of rabbit temporomandibular joint (TMJ) with disc displacement (DD) and to probe the relationship between fibrinolytic activity and cartilage remodeling.</p><p><b>METHODS</b>Disc displacement of right joints was performed in 36 of 78 rabbits under investigation. The animals were sacrificed at 4 days and 1, 2, 4, 8 and 12 weeks after surgery, respectively. The right joints of these animals were harvested and processed for the examination of mRNA expression of uPA and PAI-1 in articular cartilage using in situ hybridization techniques.</p><p><b>RESULTS</b>The expression of uPA and PAI-1 was co-expressed weakly in the chondrocytes from transitive zone to hypertrophic zone and mineralized zone, while no hybridizing signals were shown in proliferative zone and superficial zone in control rabbits. The most striking was the up-regulation of uPA and PAI-1 mRNA in 4-day rabbits postoperatively at the onset of cartilage degeneration. The strongest hybridizing signals for uPA and PAI-1 were seen in 2-week rabbits postoperatively. After 2 weeks, the expression of uPA and PAI-1 began to decrease and reached nearly normal level at 12 weeks.</p><p><b>CONCLUSIONS</b>The expression of the uPA/PAI-1 system coincides with the pathological changes in condylar cartilage after DD. The uPA/PAI-1 system may be one of the essential mediators in articular cartilage remodeling.</p>

Expression related to vascular endothelial growth factor C and induced nitride oxide synthesizase in lymph node micrometastasis of oral squamous cell carcinoma / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the relationship of vascular endothelial growth factor C (VEGF-C) and induced nitride oxide synthesizase (iNOS) expression in lymph node micrometastasis of oral squamous cell carcinoma.</p><p><b>METHODS</b>Samples were obtained from 47 cases of oral squamous cell carcinoma and 15 cases with normal oral mucosa, VEGF-C and iNOS mRNA expression were detected by RT-PCR method. Lymph node micrometastasis of 10 normal lymph nodes and 355 lymph nodes from 47 cases of oral squamous cell carcinoma was detected with immunohistochemical reaction in cytokeratin antibody.</p><p><b>RESULTS</b>The percentages in tumors with higher expression were 57.4% for VEGF-C, 68.1% for iNOS (P < 0.05). They were significantly higher than that of normal groups. Significant positive relationship was found between VEGF-C and iNOS (P < 0.01). The positive rate of cytokeratin (CK) was 48.9%. Significant positive relationship was found between VEGF-C and CK, iNOS and CK (P < 0.01). The expression rates of CK in positive group of VEGF-C and iNOS were 63.0%, 65.6% respectively, and were significant higher than negative groups.</p><p><b>CONCLUSION</b>Expression of VEGF-C and iNOS in lymph node micrometastasis of oral squamous cell carcinoma is significant related.</p>

The relationship between lymphangiogenesis and cervical lymph node micrometastasis in oral squamous cell carcinoma / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To probe the relationship between lymphangiogenesis and cervical lymph node micrometastasis in oral squamous cell carcinoma.</p><p><b>METHODS</b>The microlymphatic vessel density was detected with enzyme histo-chemical method in 47 cases of oral squamous cell carcinoma and 10 cases of normal oral mucosa; 355 lymphnodes were detected with immunohistochemically using monoantibody AE3.</p><p><b>RESULTS</b>The mean MLVD was 14.04 +/- 6.92 in tumor group, or 5.48 +/- 2.62 in normal group. The difference was (P < 0.001). The percentage of tumor with expression CK was 48.9%. The mean MLVD was 16.94 +/- 5.43 in CK positive group, or 11.26 +/- 5.00 in CK negative group, There was difference significant (P < 0.001).</p><p><b>CONCLUSIONS</b>Lymphangiogenesis plays a key role in cervical lymph node micrometastasis of oral squamous cell carcinoma.</p>

Disc-like changes and type II collagen mRNA expression in the bilaminar zone of rabbit temporomandibular joint following disc displacement / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the adaptive alteration in bilaminar zone of rabbits' temporomandibular joint following disc displacement.</p><p><b>METHODS</b>Twenty-six Japanese white rabbits were used in this study. Among these rabbits,6 were used as controls. The right discs of other 20 rabbits were displaced anteriorly by operation. Four of these rabbits were killedatn 1, 2, 4, 6 and 8 weeks respectively after surgery. The TMJS were studied by HE staining, Alcin bluen staining and in situ detection of type II collagen mRNA expression.</p><p><b>RESULTS</b>There appeared cartilage metaplasia after one week following disc displacement. Typical chondrocytes could be found in the bilaminar zone. The new chondrocytes expressed type II collagen.</p><p><b>CONCLUSIONS</b>The bilaminar zone of TMJ will be remodeled following disc displacement and become a disc-like tissue to function as a disc.</p>